In the optical communications field, an optical fiber is used to transmit signal light, and an optoelectronics chip is used to, for example, modulate, route, and multiplex received signal light. To obtain a greater optical communication capacity, an optical fiber array (which includes a plurality of optical fibers) is usually used to transmit signal light. A pitch between adjacent optical fibers in the optical fiber array is relatively large due to reasons such as a manufacturing technique. However, a pitch between adjacent optical waveguides in an optoelectronics chip (which includes a plurality of optical waveguides) is relatively small. As a result, the optical fibers in the optical fiber array cannot be connected to the optical waveguides in the optoelectronics chip. To couple signal light in the optical fiber array to the optoelectronics chip, an optical coupling connector usually needs to be used.
The optical coupling connector is used to connect the optical fiber array and the optoelectronics chip, to input, into the optoelectronics chip, signal light transmitted by the optical fiber array. However, losses of the signal light occur when the signal light is transmitted in an optical fiber and the optical coupling connector due to causes such as absorption and scattering. There are two commonly used solutions at present for compensating for the losses of the signal light. In a first solution, an erbium-doped optical fiber amplifier (EDFA) is used instead of the optical coupling connector. The EDFA is connected between the optical fiber array and the optoelectronics chip, to amplify and couple the signal light. A disadvantage of the first solution is as follows: Because a volume of the EDFA is relatively large and each optical fiber needs to independently use one EDFA, when a quantity of optical fibers in the optical fiber array is relatively large, a coupling difficulty when EDFAs are used is relatively great. In a second solution, a semiconductor optical amplifier (SOA) is integrated into the optoelectronics chip, and the signal light received by the optoelectronics chip is amplified by using the SOA. A disadvantage of the second solution is as follows: Because a thermal effect of the SOA is obvious, a temperature controller needs to be installed in the optoelectronics chip. In addition, because a preparation technique of the SOA is incompatible with a technique of a complementary metal oxide semiconductor (CMOS) in the optoelectronics chip, integrating the SOA into the optoelectronics chip encounters a relatively great technical difficulty.